Ansible: How to update directory value in the file

Question

I use following:
directory file: dir.yml

x86_64:
  alpine:
    update:
    version: 3.14.0

aarch64:
  alpine:
    update:
    version: 3.14.0 

ansible playbook:

---
- name: Playbook  
  hosts: localhost

  vars:
    new_version: 3.15.0
    update:

  tasks:
  
    - name: "Include: dir.yml"
      ansible.builtin.include_vars:
        file: dir.yml
    
    - debug:
        msg: 
          - "{{x86_64.alpine.version}}"
          - "{{new_version}}"
          - "{{update}}"
    
    - set_fact:
        update: "{{'true' if x86_64.alpine.version < new_version else 'false'}}"

Question:
How to update following field in the dir.yml

x86_64:
  alpine:
    update: true <------

I was trying to use ansible.builtin.replace or ansible.builtin.lineinfile but still cannot figured out

Does anyone have any solution for this

Answer 1

Read the file into a dictionary

    - ansible.builtin.include_vars:
        file: dir.yml
        name: arch

gives

  arch:
    aarch64:
      alpine:
        update: null
        version: 3.14.0
    x86_64:
      alpine:
        update: null
        version: 3.14.0

Update the dictionary

    - ansible.builtin.set_fact:
        arch: "{{ arch|combine({'x86_64': _x86_64}) }}"
      vars:
        _update: "{{ arch.x86_64.alpine.version is version(new_version, '<') }}"
        _x86_64_alpine: "{{ arch.x86_64.alpine|combine({'update': _update}) }}"
        _x86_64: "{{ arch.x86_64|combine({'alpine': _x86_64_alpine}) }}"

gives

  arch:
    aarch64:
      alpine:
        update: null
        version: 3.14.0
    x86_64:
      alpine:
        update: true
        version: 3.14.0

and rewrite the file

    - ansible.builtin.copy:
        dest: dir.yml
        content: |-
          {% for k,v in arch.items() %}
          {{ k }}:
            {{ v|to_nice_yaml }}
          {% endfor %}

gives

shell> cat dir.yml
x86_64:
  alpine:
    update: true
    version: 3.14.0

aarch64:
  alpine:
    update: null
    version: 3.14.0

---

Notes

• The empty values of attribute update will be replaced by 'null'. This shouldn't be a problem because 'null' translates to boolean 'false' in YAML.

• The values of updated attributes update will be replaced either by 'true' or 'false'.

• The tasks are idempotent as a result of the previous two notes.

• You might want to update more items. For example, given the variable

    new_version:
      x86_64: 3.15.0
      aarch64: 3.14.0

The task below updates the dictionary

    - ansible.builtin.set_fact:
        arch: "{{ arch|combine({item: _arch}) }}"
      loop: "{{ new_version.keys()|list }}"
      vars:
        _update: "{{ arch[item].alpine.version is version(new_version[item], '<') }}"
        _arch_alpine: "{{ arch[item].alpine|combine({'update': _update}) }}"
        _arch: "{{ arch[item]|combine({'alpine': _arch_alpine}) }}"

gives

  arch:
    aarch64:
      alpine:
        update: false
        version: 3.14.0
    x86_64:
      alpine:
        update: true
        version: 3.14.0